What Are DAWs, Audio Plugins, and MIDI Controllers?

Digital Audio Workstation (DAW)

A digital audio workstation (DAW) is an electronic device or
software application used to record, edit, and produce sound files.
DAWs are controlled with a user interface. Most DAWs allow MIDI controls
to tune parameters during live editing.

In the music industry, DAWs are typically used to acquire and
save multiple tracks of audio recordings, and to mix, equalize, and
add audio effects. DAWs generally have access to libraries of sounds
and are used to create electronic music from scratch. Commercial DAWs,
such as those found in recording studios, can be hardware integrated
into computers.

DAWs are also used in the production of radio, television, film,
podcasts, games, and anywhere complex manipulation of audio signals
is needed.

DAWs generally support plugins, which are smaller pieces of
software with unique functionality, therefore expanding the abilities
of the DAW user.

Audio Plugins

Plugins are self-contained pieces of code that can be “plugged
in” to DAWs to enhance their functionality. Generally, plugins
fall into the categories of audio signal processing, analysis, or
sound synthesis. Plugins usually specify a user-interface containing
UI widgets, but the DAW interface might mask it. Typical plugins include
equalization, dynamic range control, reverberation, delay, and virtual
instruments.

To process streaming audio data, the DAW calls the plugin, passes
in a frame of input audio data, and receives back a frame of processed
output audio data. When a plugin parameter changes (for example, when
you move a control on the plugin’s UI), the DAW notifies the
plugin of the new parameter value. Plugins usually have their own
custom UI, but DAWs also provide a generic UI for all plugins.

Audio System
Toolbox™ supports code generation to the most
common plugin format, Steinberg’s VST (Virtual Studio Technology). Audio System
Toolbox also
enables you to run and test externally authored VST and VST3 plugins
directly in MATLAB®.

Musical Instrument Digital Interface (MIDI)

Musical Instrument Digital Interface (MIDI) is a technical standard
for communication between electronic instruments, computers, and related
devices. MIDI carries event messages specific to audio signals, such
as pitch and velocity, as well as control signals for parameters such
as volume, vibrato, panning, cues, and clock signals to synchronize
tempo.

MIDI controllers are devices that send MIDI messages. Common
devices include electronic keyboards or surfaces with sliders, knobs,
and buttons. For DAWs, MIDI controllers can be physical instantiations
of functionality present in the DAW. The DAW user can interact using
a keyboard and mouse and MIDI controllers.